import 'package:flutter/material.dart';

void main() {
  runApp(MyApp());
}

class MyApp extends StatelessWidget {
  const MyApp({super.key});

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        appBar: AppBar(
          title: Text("Flutter Demo", style: TextStyle(color: Colors.white)),
          backgroundColor: Colors.blue,
        ),
        body: HomePage(),
      ),
    );
  }
}

class HomePage extends StatelessWidget {
  const HomePage({super.key});

  @override
  Widget build(BuildContext context) {
    return Stack(
      alignment: Alignment.center,
      children: [
        Container(width: 400, height: 300, color: Colors.red),
        Container(width: 200, height: 200, color: Colors.yellow),
        Text("你好Flutter！"),
      ],
    );
  }
}
